【转】spring session redis 整合

【转】http://blog.csdn.net/xiejx618/article/details/42919327

参考资料:

http://projects.spring.io/spring-session/#quick-start
http://docs.spring.io/spring-session/docs/current-SNAPSHOT/reference/html5/guides/httpsession.html#httpsession-sample

spring session提供以下功能:
1.API and implementations for managing a user's session
2.HttpSession - allows replacing the HttpSession in an application container (i.e. Tomcat) neutral way
2.1.Clustered Sessions - Spring Session makes it trivial to support clustered sessions without being tied to an application container specific solution.
2.2.Multiple Browser Sessions - Spring Session supports managing multiple users' sessions in a single browser instance (i.e. multiple authenticated accounts similar to Google).
2.3.RESTful APIs - Spring Session allows providing session ids in headers to work with RESTful APIs
3.WebSocket - provides the ability to keep the HttpSession alive when receiving WebSocket messages

仅是集群session功能,都是振奋人心的.spring session是通过filter嵌入去实现的(spring security也是使用这种方式),下面是个例子.

1.主要依赖

 

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1. <dependency>  
2.     <groupId>org.springframework.data</groupId>  
3.     <artifactId>spring-data-redis</artifactId>  
4.     <version>1.4.1.RELEASE</version>  
5. </dependency>  
6. <dependency>  
7.     <groupId>redis.clients</groupId>  
8.     <artifactId>jedis</artifactId>  
9.     <version>2.5.2</version>  
10. </dependency>  
11. <dependency>  
12.     <groupId>org.springframework.session</groupId>  
13.     <artifactId>spring-session</artifactId>  
14.     <version>${spring.session.version}</version>  
15. </dependency>  

2.写一个configuration来启用RedisHttpSession,在这个配置注册一个redis客户端的连接工厂Bean,供Spring Session用于与redis服务端交互.

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1. package org.exam.config;  
2. import org.springframework.context.annotation.Bean;  
3. import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;  
4. import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession;  
5. /** 
6.  * Created by xin on 15/1/20. 
7.  */  
8. @EnableRedisHttpSession  
9. public class SessionConfig {  
10.     @Bean  
11.     public JedisConnectionFactory connectionFactory() {  
12.         return new JedisConnectionFactory();  
13.     }  
14. }  

3.写一个Initializer,主要用于向应用容器添加springSessionRepositoryFilter,顺便注册一下HttpSessionEventPublisher监听,这个监听的作用发布HttpSessionCreatedEvent和HttpSessionDestroyedEvent事件

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1. package org.exam.config;  
2. import org.springframework.session.web.context.AbstractHttpSessionApplicationInitializer;  
3. /** 
4.  * Created by xin on 15/1/20. 
5.  */  
6. public class SessionApplicationInitializer extends AbstractHttpSessionApplicationInitializer {  
7.     @Override  
8.     protected void afterSessionRepositoryFilter(ServletContext servletContext) {  
9.         servletContext.addListener(new HttpSessionEventPublisher());  
10.     }  
11. }  

4.将SessionConfig加入到org.exam.config.DispatcherServletInitializer#getRootConfigClasses,不要加到ServletConfigClasses,至于原因看http://blog.csdn.net/xiejx618/article/details/50603758文末

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1. @Override  
2. protected Class<?>[] getRootConfigClasses() {  
3.     return new Class<?>[] {AppConfig.class,SessionConfig.class};  
4. }  

5.使用例子.

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1. package org.exam.web;  
2. import org.springframework.stereotype.Controller;  
3. import org.springframework.ui.Model;  
4. import org.springframework.web.bind.annotation.RequestMapping;  
5. import javax.servlet.http.HttpServletRequest;  
6. import javax.servlet.http.HttpSession;  
7. /** 
8.  * Created by xin on 15/1/7. 
9.  */  
10. @Controller  
11. public class DefaultController {  
12.     @RequestMapping("/")  
13.     public String index(Model model,HttpServletRequest request,String action,String msg){  
14.         HttpSession session=request.getSession();  
15.         if ("set".equals(action)){  
16.             session.setAttribute("msg", msg);  
17.         }else if ("get".equals(action)){  
18.             String message=(String)session.getAttribute("msg");  
19.             model.addAttribute("msgFromRedis",message);  
20.         }  
21.         return "index";  
22.     }  
23. }  

得到这个被spring session包装过的session,像平常一样直接使用.
6.测试.先启动redis服务端.
请求:localhost:8080/testweb/?action=set&msg=123   把123通过spring session set到redis去.
请求:localhost:8080/testweb/?action=get 从redis取出刚才存入的值.

从Redis删除存入去相关的值,再次请求localhost:8080/testweb/?action=get查看结果

 

redis:

a.查询所有key:keys命令，keys *

b.根据某个key删除,使用del命令

源码例子:

http://download.csdn.net/detail/xiejx618/9369518

 

使用redis集群的一个例子:

 

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1. <dependency>  
2.     <groupId>org.springframework.data</groupId>  
3.     <artifactId>spring-data-redis</artifactId>  
4.     <version>1.7.1.RELEASE</version>  
5. </dependency>  
6. <dependency>  
7.     <groupId>org.apache.commons</groupId>  
8.     <artifactId>commons-pool2</artifactId>  
9.     <version>2.4.2</version>  
10. </dependency>  
11. <dependency>  
12.     <groupId>redis.clients</groupId>  
13.     <artifactId>jedis</artifactId>  
14.     <version>2.8.1</version>  
15. </dependency>  
16. <dependency>  
17.     <groupId>org.springframework.session</groupId>  
18.     <artifactId>spring-session</artifactId>  
19.     <version>1.1.1.RELEASE</version>  
20. </dependency>  

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1. #REDIS START  
2. redis.maxRedirections=10  
3. redis.maxWaitMillis=1500  
4. redis.maxTotal=2048  
5. redis.minIdle=20  
6. redis.maxIdle=200  
7. redis.jedisClusterNodes=192.168.1.250:6380,192.168.1.250:6381,192.168.1.250:6382  
8. #REDIS END  

 

 

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1. @Configuration  
2. @EnableRedisHttpSession  
3. public class HttpSessionConfig implements EnvironmentAware {  
4.     private Environment env;  
5.     @Bean  
6.     public JedisConnectionFactory jedisConnectionFactory() {  
7.         String[] jedisClusterNodes = env.getProperty("redis.jedisClusterNodes").split(",");  
8.         RedisClusterConfiguration clusterConfig=new RedisClusterConfiguration(Arrays.asList(jedisClusterNodes));  
9.         clusterConfig.setMaxRedirects(env.getProperty("redis.maxRedirections",Integer.class));  
10.   
11.         JedisPoolConfig poolConfig=new JedisPoolConfig();  
12.         poolConfig.setMaxWaitMillis(env.getProperty("redis.maxWaitMillis",Integer.class));  
13.         poolConfig.setMaxTotal(env.getProperty("redis.maxTotal",Integer.class));  
14.         poolConfig.setMinIdle(env.getProperty("redis.minIdle",Integer.class));  
15.         poolConfig.setMaxIdle(env.getProperty("redis.maxIdle",Integer.class));  
16.   
17.         return new JedisConnectionFactory(clusterConfig,poolConfig);  
18.     }  
19.   
20.     @Override  
21.     public void setEnvironment(Environment environment) {  
22.         this.env=environment;  
23.     }  
24. }  

 

 

 

下面顺便跟踪下实现吧:

1.注册springSessionRepositoryFilter位置在:org.springframework.session.web.context.AbstractHttpSessionApplicationInitializer#insertSessionRepositoryFilter,从org.springframework.web.filter.DelegatingFilterProxy#initDelegate可以看出会去找名为springSessionRepositoryFilter Bean的实现作为Filter的具体实现.
2.因为使用了@EnableRedisHttpSession,就会使用org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration,这个配置里注册的springSessionRepositoryFilter Bean就是SessionRepositoryFilter.即springSessionRepositoryFilter的实现为org.springframework.session.web.http.SessionRepositoryFilter
3.Filter每一次的请求都会调用doFilter,即调用SessionRepositoryFilter的父类OncePerRequestFilter的doFilter,此方法会调用SessionRepositoryFilter自身的doFilterInternal.这个方法如下:

 

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1. protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {  
2.     request.setAttribute(SESSION_REPOSITORY_ATTR, sessionRepository);  
3.     SessionRepositoryRequestWrapper wrappedRequest = new SessionRepositoryRequestWrapper(request, response);  
4.     SessionRepositoryResponseWrapper wrappedResponse = new SessionRepositoryResponseWrapper(wrappedRequest,response);  
5.     HttpServletRequest strategyRequest = httpSessionStrategy.wrapRequest(wrappedRequest, wrappedResponse);  
6.     HttpServletResponse strategyResponse = httpSessionStrategy.wrapResponse(wrappedRequest, wrappedResponse);  
7.     try {  
8.         filterChain.doFilter(strategyRequest, strategyResponse);  
9.     } finally {  
10.         wrappedRequest.commitSession();  
11.     }  
12. }  

4.从这里就知request经过了包装,httpSessionStrategy的默认值是new CookieHttpSessionStrategy(),可以猜测它结合了cookie来实现,当然里面的getSession方法也重写了.org.springframework.session.web.http.SessionRepositoryFilter.SessionRepositoryRequestWrapper#getSession(boolean)方法如下:

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1. public HttpSession getSession(boolean create) {  
2.     if(currentSession != null) {  
3.         return currentSession;  
4.     }  
5.     String requestedSessionId = getRequestedSessionId();  
6.     if(requestedSessionId != null) {  
7.     S session = sessionRepository.getSession(requestedSessionId);  
8.         if(session != null) {  
9.             this.requestedValidSession = true;  
10.             currentSession = new HttpSessionWrapper(session, getServletContext());  
11.             currentSession.setNew(false);  
12.             return currentSession;  
13.         }  
14.     }  
15.     if(!create) {  
16.         return null;  
17.     }  
18.     S session = sessionRepository.createSession();  
19.     currentSession = new HttpSessionWrapper(session, getServletContext());  
20.     return currentSession;  
21. }  

即上面的例子调用getSession会调用此方法来获取Session.而此Session是通过sessionRepository创建的,此处注入的是org.springframework.session.data.redis.RedisOperationsSessionRepository(sessionRepository的注册也是在org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration),而不是应用服务器本身去创建的.

可以继续看看org.springframework.session.data.redis.RedisOperationsSessionRepository#createSession

 

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1. public RedisSession createSession() {  
2.     RedisSession redisSession = new RedisSession();  
3.     if(defaultMaxInactiveInterval != null) {  
4.         redisSession.setMaxInactiveIntervalInSeconds(defaultMaxInactiveInterval);  
5.     }  
6.     return redisSession;  
7. }  

这里new了一个RedisSession,继续看org.springframework.session.data.redis.RedisOperationsSessionRepository.RedisSession#RedisSession()

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1. RedisSession() {  
2.             this(new MapSession());  
3.             delta.put(CREATION_TIME_ATTR, getCreationTime());  
4.             delta.put(MAX_INACTIVE_ATTR, getMaxInactiveIntervalInSeconds());  
5.             delta.put(LAST_ACCESSED_ATTR, getLastAccessedTime());  
6.         }  
7.         RedisSession(MapSession cached) {  
8.             Assert.notNull("MapSession cannot be null");  
9.             this.cached = cached;  
10.         }  
11.            

这里又new了一个MapSession并赋给了cached变量,再看org.springframework.session.MapSession片段:

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1. public static final int DEFAULT_MAX_INACTIVE_INTERVAL_SECONDS = 1800;  
2.   
3. private String id = UUID.randomUUID().toString();  
4. private Map<String, Object> sessionAttrs = new HashMap<String, Object>();  
5. private long creationTime = System.currentTimeMillis();  
6. private long lastAccessedTime = creationTime;  
7.   
8. /** 
9.  * Defaults to 30 minutes 
10.  */  
11. private int maxInactiveInterval = DEFAULT_MAX_INACTIVE_INTERVAL_SECONDS;  

从这里你可以基本猜测id就是sessionid,这个UUID就是区分不同的客户端的一个唯一标识,它会写入到客户端的cookie,session的有效时间是存在什么地方了,cached和delta都有存.最后就要看它怎么保存到redis里面去了.下面再看看如何保存到redis去:response是经过了SessionRepositoryResponseWrapper包装,SessionRepositoryResponseWrapper是OnCommittedResponseWrapper的子类,服务端一旦调用response.getWriter()就会触发org.springframework.session.web.http.OnCommittedResponseWrapper#getWriter

 

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1. @Override  
2. public PrintWriter getWriter() throws IOException {  
3.     return new SaveContextPrintWriter(super.getWriter());  
4. }  

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1. private class SaveContextPrintWriter extends PrintWriter {  
2.     private final PrintWriter delegate;  
3.   
4.     public SaveContextPrintWriter(PrintWriter delegate) {  
5.         super(delegate);  
6.         this.delegate = delegate;  
7.     }  
8.   
9.     public void flush() {  
10.         doOnResponseCommitted();  
11.         delegate.flush();  
12.     }  
13.   
14.     public void close() {  
15.         doOnResponseCommitted();  
16.         delegate.close();  
17.     }  

一旦调用out.flush或out.close都会触发doOnResponseCommitted()方法,

 

 

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1. private void doOnResponseCommitted() {  
2.     if(!disableOnCommitted) {  
3.         onResponseCommitted();  
4.         disableOnResponseCommitted();  
5.     } else if(logger.isDebugEnabled()){  
6.         logger.debug("Skip invoking on");  
7.     }  
8. }  

回来org.springframework.session.web.http.SessionRepositoryFilter.SessionRepositoryResponseWrapper#onResponseCommitted

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1. @Override  
2. protected void onResponseCommitted() {  
3.     request.commitSession();  
4. }  

再回来org.springframework.session.web.http.SessionRepositoryFilter.SessionRepositoryRequestWrapper#commitSession

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1. private void commitSession() {  
2.     HttpSessionWrapper wrappedSession = currentSession;  
3.     if(wrappedSession == null) {  
4.         if(isInvalidateClientSession()) {  
5.             httpSessionStrategy.onInvalidateSession(this, response);  
6.         }  
7.     } else {  
8.         S session = wrappedSession.session;  
9.         sessionRepository.save(session);  
10.         if(!requestedValidSession) {  
11.             httpSessionStrategy.onNewSession(session, this, response);  
12.         }  
13.     }  
14. }  

终于看到sessionRepository调用save了